Clement O Adewunmi
Drug Research and Production Unit
AJ Aladesanmi
Department of Pharmacognosy, Faculty of Pharmacy, Obafemi Awolowo University, Ile-Ife, Nigeria
Francis B Adewoyin
Drug Research and Production Unit.
Jphm AO Ojewole
Department of Pharmacology, University of Durban-West-Ville, 4000 Durban South Africa.
N Naido
Department of Pharmacology, University of Durban-West-Ville, 4000 Durban South Africa.
Abstract
The aqueous, methanol, chloroform, ethyl acetate, petroleum ether extracts of Barringtonia racemosa Blume pericarp and seed were evaluated for molluscicidal, larvicial and pisicidal activity against Biomphalaria glabrata, larvae of Aedes aegypti and fish (Clarias lazera and Tilapia nilotica) respectively. The mollusciicidal, larvicidal and piscicidal assays involved incubation of B. glabrata snails, larvae of A. aegypti and fish with extracts of the fruit and seed of B. racemosa compared with niclosamide and T. tetraptera. The pericarp extracts contain more potent molluscicidal components (LC 50 =367.3 — 625.0 ppm) than the seed extracts of the fruit (LC50= 530.53 - 704.27 ppm). The rank order of toxicity for the pericarp extracts tested was for the snails: CHCl3 extract 367.3 ppm >Ethyl acetate extract 390.3 ppm. > methanol extract 530.4 ppm > petroleum ether extract 704.27 ppm. The larvicidal active agents are higher in the seed extracts (LC50 = 588.44 — 1,604.2 ppm) than in the pericarp extracts of the fruit (LC50 = 1,507.0 — 4,000.0 ppm). The rank order of toxicity of the seed extract for the larvae of A. aegypti was: CHCl3 extract 588.44 ppm > MeOH extract 762.5 ppm > petroleum ether extract 1,244.2 ppm > Ethyl acetate extract 1,604.2 ppm. The C. lazera was more resistant to Niclosamide, aqueous extracts of the pericarp and Tetrapleura tetraptera than T. nilotica. These biological activities suggest possible role for B. racemosa in the control of snail intermediate hosts of schistosomiasis and dengue fever.
Key Words: Barringtonia racemosa, Leeythidaceae, Aedes aegypti, Dengue, Biomphalaria glabrata, mollusicides, schistosomiasis, piscicides
Nig. J. Nat Prod. And Med. Vol.5 2001: 56-58